Francisco Forriol

Triglycerides and total serum cholesterol in rotator cuff tears: do they matter?

Objective In this study, the serum triglycerides and total serum cholesterol levels in patients with rotator cuff tear were determined. Design Frequency-matched case-control study. Setting University teaching hospital. Participants 240 individuals who were operated on at our institution were included in the study. 120 patients (45 men and 75 women; mean age 64.86 years, range 40 to 83 years) who underwent arthroscopic repair of a rotator cuff tear were included in group 1. 120 patients (45 men and 75 women; mean age 63.91 years, range 38 to 78 years) who underwent arthroscopic meniscectomy for a meniscal tear and had no evidence of shoulder pathology were included in group 2 (control group). These patients were frequency-matched by age (within 3 years) and sex with patients of group 1. Main outcome measures Measurement of serum triglyceride and total cholesterol concentrations. Results When comparing the two groups, there was no difference either in serum triglyceride concentration or total serum cholesterol concentration. Conclusions There appears to be no association between serum triglyceride concentration and total serum cholesterol concentration in rotator cuff tears.

Platelet-rich plasma, rhOP-1 ® (rhBMP-7) and frozen rib allograft for the reconstruction of bony mandibular defects in sheep. A pilot experimental study

A 6 cm bony defect in the mandible of 15 sheep, 8 years old, was reconstructed using variously allograft of frozen rib, rhOP-1 (rh BMP-7), platelet-rich plasma (PRP), and a combination of frozen rib allograft and rhOP-1. The histological, histomorphometric, immunohistochemical and radiographic features of reconstruction were analysed. The animals were euthanised at 2 months postoperatively. In the control and PRP groups, no bone formation was detected. The sheep receiving rhOP-1 showed some and those receiving both rhOP-1 and allograft showed most new bone formation; in both groups this was through endochondral and also fibrous ossification. The combination of bone allograft with growth factors demonstrated osteoconductive as well as osteoinductive properties, and is appealing in the management of problem fractures.

Radiological and histological analysis of cortical allografts: an experimental study in sheep femora

IntroductionWe developed an experimental model in sheep femora to evaluate the process of cortical allograft incorporation.Materials and methodsTwenty-four sheep were divided into four groups according to the various treatments of cortical allografts as follows: fresh, frozen, autoclaved, and frozen with perforation. Periodical radiographic and histological evaluations were performed for each group.ResultsPerforated frozen allograft proved to be superior radiographically in the first stage to fresh, frozen, and autoclaved forms. Revascularization was demonstrated by both Spalteholz’s technique and histological examination. Histological analysis also showed creeping substitution, from the host bone to the allograft, which increased the reabsorption to facilitate new bone penetration, including endochondral ossification at the host-graft interface.ConclusionWe believe that endochondral ossification is probably a biological event occurring routinely during the bone healing process and that the processes of incorporation of variously treated cortical allografts differ only at the early phase of implantation.

Animal models for translational research on shoulder pathologies: from bench to bedside.

Several animal models have been used for in vivo and in vitro shoulder research. In vitro models, consisting of cadaveric specimens, are useful in providing basic understanding of the functioning of the shoulder and for biomechanical experiments. In vivo models provide the means to model living phenomena, such as tendon healing process, tendinopathy, instability, and adaptive responses to surgery. However, intrinsic differences among different species make translation to human shoulder pathologies difficult. Most of the animals used in experimental settings are quadrupeds, using the forelimbs for weight-bearing during locomotion, with no or minimal overhead activity. The various animal models already used to study shoulder pathologies are presented in this article. However, there is a lack of validation for these animal models, which provides challenge to the further research in this field.

Clinical outcome and gait analysis of ankle arthrodesis.

Background: The purpose of our study was to describe and analyze the functional outcomes of mid-term followup patients with ankle arthrodesis. Methods: Twenty patients who had an isolated ankle arthrodesis were followed for a mean of 3 years after surgery. We performed physical and functional examination, radiographic examination and CT scan. Each completed standardized, self-reported outcome questionnaires SF-36, AOFAS and Mazur scores. All subjects were evaluated with a kinetic and kinematic gait analysis and a plantar pressure study. Results: Only one patient used a cane and seven patients required an insole to walk. We observed no relation between the scores obtained. Most of the patients showed good functional results and poor life quality scores. The joints that were significantly more degenerated were the Chopart and the subtalar joints, which were affected in 16 patients in the fused limb. The kinematic parameters showed compensatory motion in the neighboring joints and the kinetic parameters studied were similar in the arthrodesis limb and the control limb. There was no significant difference between the arthrodesis limb and the contralateral limb for plantar pressures. Conclusion: Although ankle arthrodesis will help to relieve pain and to improve overall function, it is considered to be a salvage procedure that causes persistent alterations in gait, with the possible development of symptomatic osteoarthritis in the other joints of the foot. Patients and treating physicians should also expect overall pain and functional limitations to increase over time. Level of Evidence: IV, Case Series

Knee immobilization on meniscal healing after suture: An experimental study in sheep

Immobilization and nonweightbearing may influence the healing of sutured meniscal lesions in the avascular zone. In 12 sheep, 3 to 4 months of age, a 0.5-cm longitudinal lesion was made in the middle segment and posterior portion of the medial meniscus of the left knee in the avascular zone. The lesion was sutured immediately. The knees of six sheep were immobilized with a monolateral external fixator, which crossed the knee, and the knees in the other six sheep were not immobilized. The animals were sacrificed 6 weeks after the operation. Specimens from the anterior meniscus were used for histologic and vascular studies, and the posterior meniscus was used for mechanical testing. Repair was observed in two of 12 sheep in the form of fibrous tissue. Fibrochondrocytes and synovial cells were involved. Meniscal fibrochondrocytes from the nearest meniscal tissue, synovial cells from the femoral and tibial meniscal surfaces, and fibroblastic cells migrating through the suture channel provide cell access to the meniscus lesion. Sutured menisci, immobilized or not, support less than 50% of a normal load and are mechanically weak.

Knee chondral injuries: Clinical treatment strategies and experimental models

Articular cartilage has a very limited capacity to repair and as such premature joint degeneration is often the end point of articular injuries. Patients with chondral injury have asymptomatic periods followed by others in which discomfort or pain is bearable. The repair of focal cartilage injuries requires a precise diagnosis, a completed knee evaluation to give the correct indication for surgery proportional to the damage and adapted to each patient. Many of the surgical techniques currently performed involve biotechnology. The future of cartilage repair should be based on an accurate diagnosis using new MRI techniques. Clinical studies would allow us to establish the correct indications and surgical techniques implanting biocompatible and biodegradable matrices with or without stem cells and growth factors. Arthroscopic techniques with the design of new instruments can facilitate repair of patella and tibial plateau lesions.

Growth factors in cartilage and meniscus repair

Menisci and articular cartilage are easily injured but difficult to repair. Both tissues are structures of low cellular density. The cells are highly differentiated and specialised, with a limited capacity for proliferation. The main effects of growth factors on chondrocytes are stimulation of the extracellular cartilage matrix and inhibition and activation of proteases. Growth factors with anabolic effects promoting chondrogenesis and maintenance of the phenotype of the chondrocyte could be useful in the treatment of injured cartilage or meniscus. An important aspect of treatment with growth factors is their insertion into suitable scaffolds. Ongoing research is focusing on the repair of defects in articular cartilage with hyaline tissue instead of fibrocartilage, and the repair of meniscal lesions with a stronger fibrocartilage. This article examines the latest advances made in this field of regenerative medicine.

Articular cartilage degeneration after frozen meniscus and achilles tendon allograft transplantation: experimental study in sheep

PURPOSE The purpose of this study was to analyze cartilage degeneration in knees after total medial meniscectomy, transplantation of fresh-frozen meniscus allograft, and Achilles tendon allograft. TYPE OF STUDY Experimental study. METHODS We have studied the articular cartilage in the medial compartment of the left knees in 32 sheep aged 5 to 6 months, with 8 animals in each group. The study was performed after meniscectomy (group I), transplantation of fresh-frozen meniscus allograft (group II), use of fresh-frozen Achilles tendon allograft (group III), and in a control group (group IV). For the histologic study, all samples were stained with Massons trichrome and Safranine-O. Mankins score was applied to grade the histologic damage to the articular cartilage. RESULTS The group with the greatest number of degenerative changes was group III, followed by groups I and II. The percentage of thickness of cartilage detected by Safranine-O stain was found to be significantly different in both tibia and femur between the control group and the other 3 groups, but not among groups I, II, and III. The immunoreactivity of the articular surfaces in tibia and femur showed notable differences in all the groups. Collagen X was present in the degenerative hypertrophic chondrocytes in the damaged articular surfaces. CONCLUSIONS Meniscal replacement with meniscal and Achilles tendon allografts provides partial protection against articular damage after a meniscectomy.

Morphologic comparison of cervical, thoracic, lumbar intervertebral discs of cynomolgus monkey (Macaca fascicularis)

The aim was to analyze the morphological differences of the intervertebral disc and endplates at different levels. Forty-five vertebral motion segments were obtained from the spine of nine 3 to 4-year-old cynomolgus monkeys (Macaca fascicularis). From every spine, five discs were sectioned (C5-C6, T3-T4, T9-T10, L2-L3, L4-L5). In all the groups, tissue samples were collected and sections were stained with Massons trichrome, Safranine-O and van Giesons connective tissue stain to analyze the intervertebral discs. Immunohistochemistry was performed, using specific antibodies to detect collagens I and II. The intervertebral disc height, the maximum nucleus pulposus height, the superior and inferior endplate heights were histomorphometrically measured and different indexes were calculated to compare the differences between specimens of the same animal and between discs of the same level, and finally the differences between groups of discs of different levels. There were no differences existing in annular fibers anchoring on the endplate between discs of different levels. A positive immune reaction for type I collagen was observed in the longitudinal ligaments and in the annular region adjacent to them. Collagen II immune reactivity was found in the annulus close to the nucleus pulposus, in the endplates and in the nucleus. There were no differences between discs of different levels in the collagen I and II localization. The height of the discs varied along the spine. The smallest value was measured in T3-T4, with a larger increase caudally than cranially. The highest value was measured in L2-L3. A cervical disc was 55% the height of a lumbar one. The endplate height increased along the length of the spine. The inferior EP was always higher than the superior. The study provides a detailed structural characterization of the intervertebral disc and may be useful for further investigations on the disc degeneration process.